It seems like it would be an issue that the developers would like to prioritize, since it makes their app basically useless for anyone with any decently-sized library. I'll also throw in that the app will take a noticeable amount of CPU even when seemingly idling, with no visible loading of anything or any indication that the app is doing anything at all. I dare say that the app is badly written as it currently stands and that itch.io's continuing to keep the app as-is (and even their releasing it in its current state) shows that they just don't care.